According to Alexander, police were notified on February 16 about the threat being made against East High School. Staff within the Rochester City School District called police at 5:08 p.m about a threat posted on the East High School Facebook page. The threat said, "I’m coming tomorrow morning and I’m going to shoot all of ya bitches.”

RPD Deputy Chief La'Ron Singletary said it took investigators days to arrest track down because she made the threats from a fictitious social media account. It took time for investigators to track down the person to whom the account belonged.

When officers responded to the home of Abigail Hernandez on February 20, they said they found a shotgun inside the home. Police did not clarify if the shotgun was registered to Hernandez or anyone living at the home in which it was discovered.

Hernandez was arrested and charged with making a terroristic threat. She was remanded to the Monroe County Jail at the time in lieu of $15,000 bail.

As officers were investigating, Immigration and Customs Enforcement (ICE) agents determined Hernandez was an illegal immigrant who was in the United States under the Deferred Action for Childhood Arrivals (DACA) program.

The DACA program was created under the Obama administration in 2012. The program stipulates that certain people who were brought to the U.S. as children and meet a series of strict guidelines will be eligible to have deferred action for at least two years, with the possibility for renewal. Deferred action refers to a delay in the individuals' prosecutorial status. It does not mean they are given lawful status as U.S. citizens.

Hernandez was moved to a federal detention facility in Batavia and will be held there until a hearing is scheduled.

Alexander said he is unsure if Hernandez is being charged as an adult. She has no prior arrests.

"The quick thinking of school staff and the tenacious work of the investigators of the police department following through on this Facebook post lead to the arrest of Abigail Hernandez and the recovery of a shotgun," a statement from the Rochester Police Department said.

Singletary said this serves as a reminder for people everywhere that if they see something, they should say something.

Hernandez is not a student at East High School. When asked why a 21-year-old woman would be a student in the Rochester City School District, city officials would not clarify.

East High School Superintendent Shaun Nelms released a statement Friday evening on the threat:

Sadly, in wake of the recent Parkland, Florida tragedy, schools across the country have been grappling with social media threats intended to instill fear and anxiety. While we cannot comment on this particular police investigation around a threat made to East, I want to stress how fortunate we are to be part of a community in which the police department works closely with schools to ensure the safety of the entire school community. We remain very grateful to the Rochester Police Department for their partnership and for keeping us well informed throughout the entire process. Their presence on campus last week and their guidance on how to best keep staff and students safe during this efficient, successful police investigation reiterates their ongoing support. As always, the safety of students and staff is our top priority.